Biked this trail 7-16-2018. Not much traffic on a Monday mid-day. We have hybrid bikes, skinny tires would be a problem. Tunnel is no problem, lights not needed. Eastern half of trail is packed rock or dirt, western half is paved. There was a short section mid-trail where the dirt trail became narrow and close to the edge, as inexperienced trail riders we walked our bikes through this, otherwise an easy ride. The paved half was a slight grade uphill but easy biking because the grade is so gradual. On the return just for fun we coasted the first four miles without pedaling! Entire trip took about 3 1/2 hours including a delightful picnic on the lake.